Why not? Run a client in a Tails OS environment or some kind of anonymized remote VM configuration. Fetch all market-related events from a bunch of decentralized TOR relays (or over other anonymizing networks). A proper open and free market to buy/sell whatever you want. Could even do local markets over e.g. lorawan if your government shuts down your internet access.
Discussion
one word
reputation
The problem is reputation in the presence of sibyl attacks.
Seller accounts on silk road had a 100$ fee to create the account and escrow. List, discover and sell is not a problem. Problem is cheaters.
What about nostr:npub1yul83qxn35u607er3m7039t6rddj06qezfagfqlfw4qk5z5slrfqu8ncdu , nostr:npub15369wu3wzzar5fclhecyqfv683x69n6nhlg7rxqnsg2dydgxflpq3apswl o robosat and other P2P marketplaces, do they have a way to highlight reputation and avoid cheaters trying sibyl attacks?
And if it works for trading #Bitcoin it could work for trading other stuff, as well?